I made a few covers plain like this one...
Then I decided to add sides to the edges of one of the covers and lets just say it was such a big hit that my little chi was more interested in getting straight to sleep rather than posing for a photo! I had to turn the whole bed around to try and get a cute photo! LOL
I made the sides by making a long tube of fabric and stitched it to the cover before filling with stuffing. I then stitched the ends closed by hand. There is slightly less stuffing at the corners to allow them to sit better. I didn't bother with pattern matching when I cut these out and it wasn't until after I took these photos that I realized that the fabric patterns almost match perfectly!
If you have made any of these I would love to see your photos!